Drilling equipment



United States Patent Ofilice Patented July 28, 1959 DRILLING EQUIPMENT William E. Clavier and Raymond F. Benight, Portland, and George H. Eaton, Beaverton, Oreg.

Application October 2, 1956, Serial No. 613,476

3 Claims. (Cl. 2554.4)

This invention relates to drilling apparatus and more particularly to apparatus usefiull for drilling wells such as are used in the exploration and production of oil, water, gas, sulphur and the like. The apparatus possesses a number of novel features which contribute to the overall efficiency and utility of the equipment.

Generally, it is an object of this invention to provide a novel means for motivating the cutting portions of the tool, characterized by simplicity and ability to con tinue operation as obstructions are encountered by the tool.

This invention features the use of a fluid motor and, more particularly, a piston-cylinder device disposed within the interior of the housing of the drilling tool for actuating the cutting elements mounted on the tool. The fluid motor provides a convenient means for actuating the cutting elements as well as a means for flushing or rinsing the cuttings created by the tool, the flushing fluid employed by the tool being composed, at least in part, of exhaust fluid from the fluid motor. By using the fluid for driving the motor and flushing the well cuttings, the need for a separate source of power is eliminated. It is, therefore, another object of this invention to provide a drilling tool which is powered by a fluid motor and, more particularly, a reciprocating piston-cylinder, the piston being directly connected by means of a suitable linkage to the reciprocating cutting elements so that power may be transmitted from the motor to the cutting mechanism without the necessity of rotary parts and gears.

Another object is to provide a fluid motor having a reciprocating motor element for a drilling tool wherein the fluid motor includes a control mechanism operable to induce reciprocation of the motor element independently of the position of the motor element. Further, it is an object to provide such a fluid motor wherein the reciprocations of the motor element is determined by the rate of the flow of fluid through the motor. And still further, it is an object of this invention to provide with a drilling tool having abrading' edges which reciprocate transversely of the well bore drilled by the tool, a fluid motor having a reciprocating motor element which reciprocates longitudinally of the drilling tool, the momentum changes occurring in the motor element being accompanied by reactionary longitudinal reciprocation of the tool housing so as to produce a certain amount of impact cutting by the tool.

Another object of this invention is to provide a drilling tool of the type described which includes a means for draining the drill stem prior to lifting the apparatus from the well bore, thereby expediting the removal of the equipment from the well bore.

These and other objects and advantages are attained by the present invention, various novel features of which Will become more fully apparent when the following 2 description is read in conjunction with the accompanying drawings, wherein:

Fig. 1 is a sectional view of the upper part of a drilling tool according to this invention; v

Fig. 2 is a sectional view of the middle part of. the drilling tool of Fig. 1;

Fig. 3 is a sectional view of the lower part of the drilling tool of Figs. 1 and 2;

Fig. 4 is an end view, partly simplified, of the cutting mechanism employed in the tool; and

Fig. 5 is a side view of a portion of a valve part used in the apparatus.

Before a complete description of the figures is entered into, it is pointed out that Fig. 2 should be visualized as a continuation of Fig. 1, and Fig. 3 should be visualized as a continuation of Figs. 1 and 2, the tool normally occupying, in operation, a vertical position with the upper part of Fig. 1 constituting the top of the tool and the lower part of Fig. 3 the bottom of the tool.

Referring to the drawings, an embodiment of this invention comprises in general a drill tool, indicated generally at 5, including a housing 6 which carries at its lower end a cutting mechanism 7 and is connected at its upper end to a conventional drill stem indicated at 8. The drill stem is provided with a passage 9 through which drilling flush fluid which may be conventional material, such as mud or the like, is delivered to the interior of the drill tool. Housing 6 is comprised of a number of housing segments which may be disconnected to accommodate access to the interior of the tool, namely lower segment 10 intermediate wall segments 11, 12, 13, and 14, upper segment 15, and spanning segment 16, the various segments being connected to one another by means of suitable threaded portions presented at appropri-ate ends of the segments.

In the embodiment illustrated, housing 6 of the drilling tool is connected to drill stem 8 so that the housing may be rotated relative to the drill stem about an axis extending longitudinally along the housing and in a manner which also enables pivotal movement between the housing and drill stem. Thus, in Fig. l, threaded to the lower end of drill stem 8 is an adapter or mounting portion 17 which includes a block portion 18 and a plate 19 afiixed to block 18 as by nut and bolt assemblies 20. Seated within a cavity 21 formed at the lower portion of the adapter, is the ball end 22 of a pivot member 23. The lower end of pivot member 23 is slidablyv received by housing 6, the housing during normal operation remaining suspended from pivot member 23 at or somewhere below its upper limit position relative to the pivot member determined by the nose of upper segment 15 of the housing portion striking the shoulder 24 presented by the ball end of pivot member 23. Plate 19 has formed therein a taper 26 located above the nose of the housing portion which accommodates laterally disposed portions of the nose when the housing is swung about ball end 22.

Encircling the lower end of pivot member 23 is a compression spring 27 with its lower end seated on a nut 28 secured to a threaded portion of the pivot member and its upper end seated on the upper, inner surface of housing segment 15.v Nut 28 may be turned to adjust tbe'compression of compression spring 27 and, in

this manner, the position of the housing portion on pivot fluid communication with passage 9 of the drill stem. Drain passages 32 in the pivot member and drain passages 33 in the housing are provided to enable the drill stem to drain when it is desired to remove the drilling equipment from a well bore. Nut 28 is adjusted so that the weight of the housing and the mechanism contained therein is suflicient to cause the housing to move'to a position on pivot member 23 when the gear is removed from a well wherein drain passages 32 and 33 are in registry.

Mounted within the housing is a fluid motor mechanism, indicated generally at 34, connected by a linkage system, indicated at 36, to cutting mechanism 7.. In the embodiment shown, the fluid motor includes a fluidactuated piston or motor element 37 which during operation of. the motor reciprocates longitudinally of "the housing, the reaction forces imparted to housing 6 by the reciprocal movement of the piston within the housing tending to induce longitudinal reciprocations of the housing which contribute to the cutting action of cutting mechanism 7.

More specifically, interposed between conduit 29 of pivot member 23 and piston 37 is an inlet or delivery conduit system, indicated generally at 38, wherein fluid under pressure is distributed, by means of a valve 39, alternately to opposite sides of piston 37 thereby to induce reciprocation of the piston.

Inlet conduit system 38 includes a stem portion 41 slidably received within the interior of pivot member 23 so as to enable reciprocal movement of the housing and conduit system relative to pivot member 23. Stem portion 41 is connected at its lower extremity to a conventional adjustable valve 42, the outlet terminals of control valve 42 being connected to a relief conduit 43 and a conduit 44. By adjusting control valve 42, the amount of fluid exhausted through the relief conduit or the amount of fluid passing through the conduit 44 may be controlled.

Relief conduit 43 is connected at its lower end to a pair of conduits 57 and 58. Conduits 57 and 58 extend downwardly through the interior of the housing with their outlet portions adjacent cutting mechanism 7, as at 70 and 75, the fluid ejected from these conduits acting as a flush or rinse fluid for cuttings produced by cutting mechanism 7.

Conduit 44 contains an expanding or bell portion at its lower extremity which is internally threaded as at 45 and connected at this threaded portion to a cylindrical sleeve segment 46. Rotatably carried within sleeve segment 46 is a direction vane 47. As shown, vane 47 comprises a convolute part 48 affixed to a shaft 49, shaft 49 being rotatably mounted at its upper end in a mounting portion 51 extending between and secured to opposite interior sides of conduit 44, and rotatably mounted at its lower end in a base or mounting portion 52 integrally formed with sleeve segment 46. Vane 47, which is affixed to shaft 49 in any suitable manner, has its bottom edge abutting valve part 39, valve part 39 in turn being atfixed to shaft 49 for rotation therewith with its lower end abutting a bearing member 50. Valve part 39, and the lower extremity of sleeve segment 46, are provided with suitable passages, as will be described hereinbelow, for directing the flow of fluid which passes downwardly through sleeve segment 46. In flowing downwardly through the sleeve segment past convolute part 48, rotation of the vane and valve part 39 is created which serves to control the direction of fluid discharge from sleeve segment 46. Valve 47 functions as a valve motor adjusting valve part 39, the valve motor and valve part together comprising motor control mechanism for motor 34 in the apparatus.

Mounting portion 52, which has been partially broken away in the drawings, extends downwardly through housing 6, presenting at its lower extremity and integral therewith a cylinder sleeve portion 60 which accom modates piston 37. The base of cylinder sleeve portion 60 carries about its extremity a flange 61. Across the base of cylinder sleeve portion 60 and extending outwardly beneath flange 61 is a head plate 59. Flange 61 and head plate 59 are suitably afixed to an interior shoulder of housing segment 13, as by screws 62, thereby securing sleeve 60, mounting portion 52, and sleeve segment 46 within the housing. Piston 37 reciprocates in sleeve portion 60 by reason of pressure fluid applied alternately to opposite sides of the piston, the piston and cylinder constituting a double acting fluid ram in the device.

The conduit system providing for the delivery of pressure fluid selectively to opposite sides of piston 37, and for the exhaust of fluid from the nonpressurized side of the piston, includes a conduit segment 71 connecting the interior of the lower extremity of cylinder sleeve portion 60 to the interior of one side of sleeve segment 46 and an exhaust conduit segment 72 connected to the interior of sleeve segment 46 above conduit segment 71 with its outlet portion terminating in conduit 57 at terminal 55. A similar pair of conduit segments, segments 73 and 74, connect the interior of the other side of sleeve segment 46 to the interior of the upper extremity of cylinder sleeve portion 60, and provide an exhaust conduit for this other side of the sleeve segment 46, respectively. Exhaust conduit segment 74 has its outlet portion terminating in conduit 58 at terminal 56. The downward flow of fluid which under operating conditions normally exists in conduits 57 and 58 tends to aid the exhaust of fluid from the unpressurized side of piston 37.

Valve part 39, as may be seen with reference to Figs. 1 and 5, includes at oneof its sides a cutout portion 76 cut transversely across the valve part with the outer edges of the cutout portion lying substantially along diametrically opposed portions of the valve part, the cutout portion serving for rotation of the valve part through an angle of about to connect the upper extremities of conduit segments 71 and 72, and for rotation through a subsequent 180 angle to connect the upper extremities of conduit segments 73 and 74. A second cutout portion 77 lying transversely of the valve part with its outer edges lying substantially along diametrically opposed portions of the valve part, is formed along the opposite side of the valve part. A passage 78 lying generally longitudinally along the valve part connects the interior of sleeve segment 46 with cutout 77. Cutout 77, during rotation through an angle of about 180, connects the upper extremity of conduit segment 71 to the interior of sleeve segment 46 and through a subsequent 180 angle connects the upper extremity of conduit segment 73 to the interior of sleeve segment 46.

Connected at one of their. ends to conduit segments 71 and 73 are relief conduits 79 and 81, respectively, these relief conduits being connected at their other ends to a common exhaust conduit 82. The outlet portion of exhaust conduit 82 (not shown) is placed adjacent cutting mechanism 7 so that fluid ejected from the conduit will serve to flush the cuttings produced by the cutting mechanism. In each of the relief conduits.79, 81 is a one-way pressure relief valve, 83 and 84, respectively, which may be adjusted to allow the escape of fluid through the valves and conduit 82 whenever the pressure within conduits 71 and 73 reaches a certain level. By providing these relief valves, the flow of fluid downwardly through sleeve segment 46 is assured irrespective of whether piston 37 temporarily locks up by freezing up of the cutting mechanism 7. This enables direction vane 47 to be rotated at all times by reason of the flow of fluid occurring downwardly through sleeve segment 46, regardless of the position of piston 37, so that reciprocation of the piston tends to be induced independently of the position of the piston, pressure fluid at all times being alternately subjected to opposite sides of the piston.

Piston 37 generally is of conventional construction,

5 having a piston head 86 slidably mounted within cylinder sleeve portion 60 and a piston rod 87 aflixed to the piston head. Suitable packing for the rod is retained by a nut 90.

Piston rod 87 is slidably mounted intermediate its ends in a threaded sleeve 88 which is screwed into an accommodating threaded bore extending through the center spanning segment 16. Affixed to piston rod 87 above and below the outer ends of sleeve 88 are a pair of retainer members 89 and 91, respectively. The stroke of piston 37 is determined by the inwardly disposed surfaces of these retainer members striking the outer ends of sleeve 88. A pair of springs 92 and 93 encircling the piston rod with their outer ends seated on members 89, 91 are included to insure smooth operation of the piston and assist in regulating the stroke frequency of the piston. The inwardly disposed ends of springs 92, 93 are seated on nuts 94, 96 which are screwed onto threaded portions of sleeve 88 and are adjustable thereon. The springs, it will be noted, are interposed between the piston rod and the housing, and serve to urge piston 37 to a rest position in cylinder sleeve 60 in the absence of pressure fluid in the motor 34.

Concerning a more detailed explanation of cutting mechanism 7, referring to Figs. 3 and 4, pivoted to lug portions 99 and 100 carried by lower housing segment 10, on a pivot pin 101, are a pair of cutting levers or elements 106 and 107. Levers 106, 107 constitute a sectional cutting mechanism carried at the base of the housing for the drill tool. Pivot pin 101 extends transversely across the face of housing segment 10, and levers 106 and 107 are retained on the pin in a suitable manner, as by nuts 103, 104, the two levers being spaced from each other by a spacer member 102. Each of the levers has afiixed to its outer end a cutting bit, indicated at 108 and 109, respectively. The inner ends of levers 106, 107 are link connected, as by links 110 and 111, to rod 87, links 110, 111 being pivotally connected at their ends to levers 106, 107 and rod 87. The pivot connection between the piston rod and the cutting levers supplied by links 110, 111 enables a pivotal movement of the cutting levers about pivot pin 101 to be produced in response to reciprocal motion of piston rod 87. This pivotal movement of the cutting levers in turn produces an oscillatory motion of the cutting or abrading edges presented at the periphery of the cutting bits, so that in operation they reciprocate transversely of the well bore produced by the drilling tool.

It should be noted that the distance between pivot pin 101 and the pivot connection of levers 106, 107 with the pivot links 110, 111 is greater than the distance between the periphery of the cutting bits and pivot pin 101. By so proportioning levers 106, 107, the force delivered by piston rod 87 is multiplied during its transmission to the periphery of cutting bits 108, 109.

Each of the cutting bits 108, 109 is shaped generally in the manner of a quarter of a sphere. Attention is drawn to the fact that the radial center of each cutting bit (point 112 for bit 109) is located downwardly and to one side of the center of pivot pin 101 so that one bit in its extended position protrudes outwardly to one side of the tool and the other of the bits protrudes outwardly to the other side of the tool. This position of the bits is indicated in solid lines in Fig. 4, the bits being movable from this position to the position generally indicated in dotted lines in Fig. 4. The bits are moved by levers 106, 107 simultaneously in opposite directions by reason of the scissors action produced by the levers.

As described hereinfore, piston 37 and rod 87 are slidably mounted for reciprocation between two limit positions, as determined by the ends of threaded sleeve 88 and retainer members 89, 91. In moving between these two limit positions, which may be considered as first and second limit positions, the lower end of rod 87 and the inner ends of links 110, 111 move from a position above the pivot centers of the pivot connections between links 110, 111 and levers 106, 107, to a position lying below these pivot centers. That is, the inner ends of links 110, 111 move through overcenter positions relative to these pivot centers. In this manner levers 106, 107 move back and forth twice for each complete reciprocation of the piston and piston rod, thereby to create a maximum amount of abrasive action in the bits.

About the outer periphery of each of the bits are a number of teeth, indicated at 113, the teeth serving as the abrading edges for the bits. The offset position of the cutting bits tends to impart rotation to the tool about an axis lying longitudinally along the drilling tool during operation of the cutting mechanism. This rotation, which is accommodated by pivot member 23, better enables the drilling tool to produce a fully dimensioned well bore.

Referring to Fig. 3, secured to the interior of the housing portion for the drilling tool at the lower portion thereof, as by screws 116, is a weight member 117. Weight member 117 may be inserted if it is desired to add weight to the drilling tool in certain drilling operations. The particular weight member selected would depend upon the particular drilling job being performed.

Since the motor element or piston 37 which is used to drive the cutting mechanism reciprocates longitudinally relative to the drilling tool, in addition to the rotational movement hereinabove described and the transverse oscillatory motion ofthe abrading edges of the cutting mechanism, a certain amount of longitudinal reciprocation is present during operation in housing 6, this reciprocal movementbeing the reaction force set up by reciprocations of the motor element within the housing. The combination of reciprocal motion, transverse oscillatory motion, and rotary motion, which is present in the drilling tool of this invention, all contribute to the efliciency of the drilling tool in producing well bores.

From the foregoing, it should be apparent that there has been described herein a well drilling tool which is relatively simply constructed and which may be employed to drill well bores of considerable depth with reduced operational difliculties. The direction taken by the drilling tool in progressing downwardly is determined by gravitational pull upon the drilling tool, the tool tending to progress vertically downwardly without the tendency of curving from the vertical by reason of the corkscrew motion which attends the use of conventional rotary drilling systems. However, as discussed hereinabove, some rotary movement is provided for, and this rotary movement of the drilling tool, together with the longitudinal reciprocations of the tool which also tend to be present, increase the efiiciency of the cutting action employed by the drilling tool.

By employing a fluid motor mechanism activated by the flushing fluid coming downwardly through the drill stern, cuttings produced by the cutting mechanism are conveniently flushed or rinsed from the well bore. The device herein described is particularly well adapted to work itself free when the cutting mechanism of the tool tends to freeze within the drill bore. That is, regardless of the position of piston 37, reciprocal movement tends to be induced into the piston by the action of the motor control mechanism or valve part 39. The motor control mechanism, in turn, is controlled by the rate of fluid flow through the tool which may be conveniently adjusted as desired.

It should also be noticed that there has been provided structure which enables the drill stem to be drained prior to the removal of the drilling tool from a well bore. Although a limited amount of reciprocation normally occurs in housing 6, draining of the drill stem does not occur until the housing is protracted a sufiicient distance from pivot member 23 to enable the drainage conduits to come into registry.

While there has been described an embodiment of this invention, it is apparent that changes may be made in 7 the particular embodiment illustrated without departing from the spirit of the invention. It is intended to cover all modifications of the invention which will be apparent to one skilled in the art and that come Within the scope of the appended claims.

It is claimed and desired to secure by Letters Patent:

1. In a well drilling tool adapted to be run into a well bore, said well drilling tool having a housing portion, and cutting mechanism mounted at one end of said housing portion having abrading edges for cutting obstructions encountered by said tool, fluid motor means carried Within said housing portion, said motor means comprising a double acting fluid ram having a piston element mounted for reciprocation in said housing portion, and a motor control mechanism operable to direct fluid under pressure alternately to opposite sides of said piston element independently of the position of said piston element, said motor control mechanism comprising valve means regulating the supply of pressure fluid to opposite ends of said piston element and a valve motor adjusting said valve means to admit pressure fluid alternately to opposite sides of said piston element, and means connecting said piston element to said cutting mechanism whereby reciprocation of said piston element actuates said cutting mechanism.

2. In a well drilling tool adapted to run into a well bore, said well drilling tool having a housing portion, and cutting mechanism mounted at one end of said housing portion having abrading edges for cutting obstructions encountered by said tool, fluid motor means carried within said housing portion operatively connected to said cutting mechanism for actuating the same, said motor means comprising a double acting fluid ram having a piston element mounted for reciprocation longitudinally of said housing portion, conduit means for delivering fluid under pressure to both ends of said double acting ram, and control mechanism operable to direct fluid under pressure through said conduit means alternately to opposite ends of said fluid ram, said control mechanism having valve means regulating the supply of pressure fluid to opposite ends of said fluid ram and a valve motor adjusting said valve means to admit pressure fluid alternately to opposite ends of said fluid ram, said valve motor being energized by pressure fluid flowing through a section of said conduit means, and means connecting said piston element to said cutting-mechanism whereby reciprocation of said piston element actuates said cutting mechanism.

3. In a well drilling tool adapted to run into a well bore, said well drilling tool having a housing portion, and cutting mechanism mounted at one end of said housing portion having abrading edges for cutting obstructions encountered by said tool, fluid motor means carried within said housing portion, said motor means comprising a double acting fluid ram having a piston element mounted for reciprocation longitudinally of said housing portion, delivery conduit means for delivering fluid under pressure to both ends of said double acting ram, control mechanism directing fluid under pressure alternately to opposite sides of said piston element, said control mecha nism having valve means regulating the supply of pressure fluid to both ends of said fluid ram and a valve motor adjusting said valve means to admit pressure fluid alternately to opposite ends of said ram and energized by the flow of fluid through a section of said conduit means, relief conduit means connected to said delivery conduit means between said section of said delivery conduit means and said double acting ram for diverting fluid from said double acting ram, and means connecting said piston element to said cutting mechanism whereby reciprocation of said piston element actuates said cutting mechanism.

References Cited in the file of this patent UNITED STATES PATENTS 463,880 Webber Nov. 24, 1891 471,580 Webber Mar. 29, 1892 2,002,385 Bannister May 21, 1935 2,191,356 Snell Feb. 20, 1940 2,672,847 Bergmann Mar. 23, 1954 2,780,438 Bielstein Feb. 5, 1957 2,836,395 Bielstein May 27, 1958 

